// let position: number[] = [116.2317, 39.5427] // 数组的元素都是数值类型
{

    type Position = [string|number, number]
    
    let p1: Position = [116.2317, 39.5427] 
    let p2: Position = ["116.2317", 39.5427] 


    function useState(n: number): [number, (n:number)=>void ]  {
        const fn = (n:number):void => {}

        return [n, fn]
    }


    const [state, setstate] = useState(10)

    // setstate('1')
}